Add tests for AddNewlineAction

This adds tests for AddNewlineAction

Author: akshatkarani

tests/vcs/actions/AddNewlineActionTest.py

@@ -0,0 +1,70 @@
+import unittest
+import os
+import platform
+import shutil
+from tempfile import mkdtemp, mkstemp
+
+from coalib.results.Result import Result
+from bears.vcs.actions.AddNewlineAction import AddNewlineAction
+from coala_utils.ContextManagers import retrieve_stdout
+from coalib.misc.Shell import run_shell_command
+
+
+class AddNewlineActionTest(unittest.TestCase):
+
+    @staticmethod
+    def run_git_command(*args, stdin=None):
+        return run_shell_command(' '.join(('git',) + args), stdin)
+
+    def setUp(self):
+        self.shortlog = 'file.py: Add something'
+        self.body = ('Added something, wrote some things\n'
+                     'Wrote tests\n'
+                     '\n'
+                     'Fixes #issue')
+        self.uut = AddNewlineAction(self.shortlog, self.body)
+        self.result = Result('origin', 'message')
+
+        self._old_cwd = os.getcwd()
+        self.gitdir = mkdtemp()
+        os.chdir(self.gitdir)
+        self.gitfile = mkstemp(dir=self.gitdir)
+        self.run_git_command('init')
+        self.run_git_command('config', 'user.email [email protected]')
+        self.run_git_command('config', 'user.name coala')
+        msg = self.shortlog + '\n' + self.body
+        self.run_git_command('add .')
+        self.run_git_command('commit',
+                             '--file=-',
+                             stdin=msg)
+
+    def tearDown(self):
+        os.chdir(self._old_cwd)
+        if platform.system() == 'Windows':
+            onerror = self._windows_rmtree_remove_readonly
+        else:
+            onerror = None
+        shutil.rmtree(self.gitdir, onerror=onerror)
+
+    def test_is_applicable(self):
+        applicable = self.uut.is_applicable(self.result,
+                                            {},
+                                            {'filename': 'Diff'})
+        self.assertTrue(applicable)
+
+        applicable = self.uut.is_applicable(self.result,
+                                            {},
+                                            {'filename': 'Diff',
+                                             'AddNewlineAction': True})
+        self.assertFalse(applicable)
+
+    def test_apply(self):
+        with retrieve_stdout() as stdout:
+            file_diff_dict = self.uut.apply(self.result, {}, {})
+            self.assertEqual(file_diff_dict, {'AddNewlineAction': True})
+            self.assertEqual(stdout.getvalue(), '')
+
+            new_message, _ = run_shell_command('git log -1 --pretty=%B')
+            new_message = new_message.rstrip('\n')
+            self.assertEqual(new_message,
+                             self.shortlog + '\n\n' + self.body)